Publications by authors named "Laure F"

Various pyranocoumarins, calophyllolide, inophyllums B, C, G(1), G(2) and P, from Calophyllum inophyllum (Clusiaceae) leaves of French Polynesia (Austral, Marquesas, Society and Tuamotu archipelagos) have been determined in 136 leaf extracts using a high pressure liquid chromatography-UV-diode array detection (HPLC-UV-DAD) technique. Results show a wide range in chemical composition within trees growing on eighteen islands. The use of multivariate statistical analyses (PCA) shows geographical distribution of inophyllums and indicate those rich in HIV-1 active (+)-inophyllums.

View Article and Find Full Text PDF

A novel interface that allows normal-phase liquid chromatography to be coupled with electrospray ionization (ESI) is reported. A make-up solution of 60 mM ammonium acetate in methanol, infused at a 5 microl min(-1) flow-rate at the tip of the electrospray probe, provides a sheath liquid which is poorly miscible with the chromatographic effluent, but promotes efficient ionization of the targeted analytes. Protonated molecules generated in the ESI source were subjected to tandem mass spectrometric experiments in a triple-quadrupole mass spectrometer.

View Article and Find Full Text PDF

Three new friedelane-type triterpenoids, 3,4-secofriedelan-3,28-dioic acid (1), 27-hydroxyacetate canophyllic acid (2) and 3-oxo-27-hydroxyacetate friedelan-28-oic acid (3), were isolated from the leaves of Calophyllum inophyllum (Clusiaceae) grown in French Polynesia. Their structures were established by the concerted application of 2D NMR techniques including gs-COSY, gs-HMQC and gs-HMBC.

View Article and Find Full Text PDF

Background: While cytometry is widely used in the detection of cell proteins, its application to quantitative evaluation remains problematic when target proteins or receptors are weakly expressed in cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) is a technique whose sensitivity and specificity make it appropriate for analyzing nucleic acids and thus genes expressed in cells. Combining these two techniques, we developed a method to quantify the transcript expression of the peripheral cannabinoid receptor (CB2-r) in peripheral blood lymphocyte subpopulations and in tonsillar B-cell subpopulations.

View Article and Find Full Text PDF

A new non-isotopic sandwich hybridization assay was developed to detect human immunodeficiency virus type 1 (HIV1) provirus amplified by the polymerase chain reaction. The sensitivity and specificity of this new technique using 96-well microplates as the support for the sandwich hybridization procedure and stable enzyme-linked oligomer as the detection probe were compared with those of Southern hybridization using a 32P-labelled oligomer probe. Three laboratories studied 437 peripheral blood mononuclear cell samples from 294 different subjects including both HIV1-seropositive and -seronegative individuals.

View Article and Find Full Text PDF

We determined the nucleotide sequences of two related isolates of simian immunodeficiency virus from the sooty mangabey monkey (SIVsmm) that exhibit dramatic differences in virulence. These isolates are separated by one experimental cross-species transmission, from sooty mangabey to pig-tailed macaque. The parental virus (SIVsmm9), nonpathogenic in the original host (sooty mangabeys), causes a chronic AIDS-like disease in macaques.

View Article and Find Full Text PDF

We have investigated in utero human immunodeficiency virus type 1 (HIV-1) transmission by analyzing human fetal tissues for the presence of viral DNA by means of the polymerase chain reaction (PCR). Thirty three fetal samples: thymus, spleen, and peripheral mononuclear blood cells (PMBC) were obtained at abortion (16 to 24 weeks) from HIV-1-infected asymptomatic women. The results of HIV-1-DNA detection were considered only in 9 cases where contamination of fetal samples by infected mother cells could be definitely eliminated by using primers specific for a polymorphic cellular locus.

View Article and Find Full Text PDF

The PCR technique detects HIV1 and HIV2 DNA and RNA sequences in mononuclear cells with high sensitivity. It allows therefore to analyse the mother to child HIV1 transmission. Moreover, in the near future, the quantification of the PCR products could allow the follow-up of the patients treated for HIV infection.

View Article and Find Full Text PDF

The polymerase chain reaction (PCR) assay was used to investigate the possibility of HIV1 DNA detection in uncultured peripheral blood mononuclear cells from newborn infants and children of HIV-infected mothers. HIV1 DNA sequences were detected in mononuclear cells of six of fourteen symptom-free newborn infants of seropositive mothers. Only one of these infants had detectable HIV antigenaemia.

View Article and Find Full Text PDF

The isolation from macaques of retroviruses related to human immunodeficiency virus (HIV) led to the identification of a second group of human retroviruses (termed HIV-2), which are prevalent in West Africa and closely related to the simian immunodeficiency virus (SIV). We have cloned and determined the complete nucleotide sequence of the human West African retrovirus HIV-2NIH-Z and compared it to that of a previously described strain of HIV-2 (HIV-2ROD) as well as to SIV and HIV-1. We have reached the following conclusions: (i) The HIV-2 isolates are (slightly) more closely related to each other than to SIV, compatible with their isolation from different species.

View Article and Find Full Text PDF

Acquired immune deficiency syndrome (AIDS) is an immunosuppressive disease associated with the depletion of T4 lymphocytes. Recently, an HIV-1 genome was molecularly cloned and shown to be fully infectious in vitro by transfection experiments. In this study, we show that HIV-1 can be transfected into T4 and T8 lymphocyte subpopulations and viral proteins and infectious virus particles are observed in both short- and long-term cultures.

View Article and Find Full Text PDF

New human retroviruses antigenically related to HIV and even more closely to STLV-III have been recently isolated from individuals from some West African countries. One of these viruses, HTLV-IVP, was reportedly isolated from lymphocytes of a healthy female prostitute. Another isolate, LAV-2FG, was obtained from an AIDS patient and third, SBL-6669, from an individual with lymphadenopathy.

View Article and Find Full Text PDF

We have tested the different mononuclear blood cell populations of seven patients with severe haemophilia and one patient with F VII deficiency for the presence of HBV DNA. These subjects were all polytransfused with non-heated coagulation factors; three were HBsAg positive, five HBsAg negative but anti-HBc and anti-HBs positive; HBV DNA sequences were detected in six subjects including three without detectable serum HBsAg. Furthermore the viral DNA sequences were identified in the T lymphocyte subpopulations (OKT4+ and/or OKT8+ cells).

View Article and Find Full Text PDF

We describe here several African isolates of HIV, compare them to U.S.-European prototype isolates and to each other, correlate the number of isolates with serological results, and provide insights into the disease spectrum associated with HIV infection in Africa.

View Article and Find Full Text PDF

An unusual case of cutaneous nodular T cell lymphoma evolving for 4 years with massive eosinophilia and greatly increased IgE levels is discussed. Repeated histologic and immunohistologic examinations could not ascertain malignancy because tumors were composed of a granuloma-like, highly polymorphic cellular infiltrate with mature immunotype and no significant nuclear abnormalities nor epidermotropism. T cell lymphoma was evidenced by the T cell receptor beta-chain gene study, which showed a clonal rearrangement.

View Article and Find Full Text PDF

We have investigated 38 hepatitis B surface antigen (HBsAg)-positive and 34-negative patients with acute and chronic liver disease for the presence of hepatitis B virus (HBV) DNA in peripheral mononuclear blood cells. Among the HBsAg-positive subjects HBV DNA was detected in the mononuclear cells of asymptomatic HBV carriers (2/6), patients with acute hepatitis (8/8), chronic active hepatitis (18/21), and with hepatocellular carcinoma (2/3); the viral DNA sequences were also identified in the mononuclear cells of patients with HBsAg-negative acute hepatitis (2/3), chronic active hepatitis (5/15) and hepatocellular carcinoma (5/16), some of these showing no evidence of HBV by conventional serological markers. By contrast HBV DNA was not detected after resolution of the acute viral infection.

View Article and Find Full Text PDF

A lymphotropic virus HTLV-III/LAV was recently identified as the etiologic agent of the acquired immune deficiency syndrome (AIDS). In a study of concomitant hepatitis B infections in patients with AIDS or the AIDS-related complex, DNA sequences of hepatitis B virus (HBV) were found in fresh and cultured lymphocytes from patients with AIDS even in the absence of conventional HBV serological markers. Furthermore, the restriction DNA pattern was consistent with the integration of the viral DNA.

View Article and Find Full Text PDF

The administration of 10 micrograms oestradiol to the foetus of the guinea-pig (55-65 days of gestation) causes an increase in RNA polymerase I and II activities in the nuclei of the foetal uterus. RNA polymerase I activity increased by 4 times above the control values after 120 min (p less than 0.001) whereas RNA polymerase II activity increased more rapidly, reaching 2.

View Article and Find Full Text PDF